Algae is one of the hottest new biofuel materials, with over a dozen companies attempting to make the slimy stuff a viable feedstock. Most of them rely on the natural simplicity of the organism–sun and water turn CO2 from algae into fuel–and a few, including OriginOil, use LEDs to grow algae in the dark. Now a group of researchers from the Missouri University of Science and Technology wants to take OriginOil’s technique a step further and grow algae in abandoned mines.

Old mines are actually an ideal location for algae. When algae are grown in outdoor ponds, scientists often fear that
invasive species could escape. That’s not a problem in an underground
mine, where algae can’t survive long without LED light. The mines are also inexpensive because mining companies long ago prepped the sites for use, and they have constant temperatures–a plus for efficiently growing algae. In addition to saving algae-harvesting companies cash on infrastructure, abandoned mine-grown algae can also save mining companies on cleanup since algae sequesters metals.

Still, there are some downsides. LEDs are expensive and require lots of electricity to run, so there is a danger that more energy could be used in the lighting process than is ultimately generated by the algae. That isn’t stopping the Missouri researchers. The team is experimenting with algae in artificial mines, and a real mining operation is scheduled to go online sometime in the next two to three years.